1 . 已知函数
,
,
为
图象的一个对称中心.现给出以下四种说法:①
;②
;③函数
在区间
上单调递增;④函数
的最小正周期为
.则上述说法正确的序号为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3bb5b70e41a4ace7b016706b13bcece.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67c9168200e6089ab8b7c203078025e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c84e2a02b32a01b13d65e5e9c4554c59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ce0dc28340738e090bd10d6d675d8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c05a467ddaa138590b3b56615c2c42a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17969ef32066458222c0c74a4bb896b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15615de1a6df206dbd081251f676578e.png)
A.①④ | B.③④ | C.①②④ | D.①③④ |
您最近一年使用:0次
13-14高二上·北京·阶段练习
2 . 已知函数
.项数为27的等差数列
满足
,且公差
.若
,则当
=_____ 时,
.
![](https://img.xkw.com/dksih/QBM/2014/12/29/1571939475161088/1571939480920064/STEM/075d7dd4901f45dab2296e087b09aab8.png?resizew=128)
![](https://img.xkw.com/dksih/QBM/2014/12/29/1571939475161088/1571939480920064/STEM/1ec4034d57d0415e918414717cdfe7f5.png?resizew=31)
![](https://img.xkw.com/dksih/QBM/2014/12/29/1571939475161088/1571939480920064/STEM/7a0cb9801ea64fec9823a401909d56bf.png?resizew=92)
![](https://img.xkw.com/dksih/QBM/2014/12/29/1571939475161088/1571939480920064/STEM/6d4e9a7ef73d4fe0a3cc7f0eeddec446.png?resizew=40)
![](https://img.xkw.com/dksih/QBM/2014/12/29/1571939475161088/1571939480920064/STEM/b89f23bc7123425b89dba18c4c7e50da.png?resizew=207)
![](https://img.xkw.com/dksih/QBM/2014/12/29/1571939475161088/1571939480920064/STEM/c27ecba544ff40f0959a4c0cf2c588a3.png?resizew=13)
![](https://img.xkw.com/dksih/QBM/2014/12/29/1571939475161088/1571939480920064/STEM/094d1692043c4157980fd63bd900606c.png?resizew=68)
您最近一年使用:0次